《Revealing performance of 78Li2S-22P2S5 glass ceramic based solid-state batteries at different operating temperatures》

78Li2S-22P2S5 is a sulfide electrolyte with high lithium ion conductivity and a wide electrochemical window in the Li2S-P2S5 system, making it an ideal solid electrolyte for all-solid-state lithium-ion batteries. However, the role and potential of 78Li2S-22P2S5 solid electrolytes in a wide temperature range are still not fully understood. Therefore, we constructed a solid-state battery with NCM622 as the positive electrode and 78Li2S-22P2S5 glass ceramic as the electrolyte, and deeply studied the difference in battery performance over a wide temperature range and its internal mechanism. The in-situ impedance and relaxation time distribution proved the electrochemical stability of the electrolyte in a wide temperature range, and the in-situ stacking pressure experiment observed a large volume change during the cycle at 60 °C, resulting in local solid-solid contact failure and poor cycle stability. This study provides insights into the advantages and problems of 78Li2S-22P2S5 electrolytes at wide temperatures.

https://www.sciencedirect.com/science/article/pii/S1001841722008701